Devices and methods for sensing of passages or cavities within a body, and for gathering information (e.g., image data, pH data, temperature information, pressure information), are known in the art. Such devices may include, inter alia, various endoscopic imaging systems and devices for performing imaging in various internal body cavities. Some devices transmit the collected data to an external receiving unit.
An in-vivo imaging device may include, for example, an imaging system for obtaining images from inside a body cavity or lumen, such as the gastrointestinal (GI) tract. The imaging system may include, for example, an illumination unit, such as a set of light emitting diodes (LEDs), or other suitable light sources. The device may include an imaging sensor and an optical system, which focuses the images onto the imaging sensor. A transmitter and antenna may be included for transmitting the images signals. A receiver/recorder, for example worn by the patient, may record transmitted image data and store image and other data. The recorded data may then be downloaded from the receiver/recorder to a computer or workstation for display and analysis.
A signal transmitted from an in vivo sensor may be attenuated while passing through the body tissues, due to the fact that tissues have electrical conductance. Continuous high-level transmission, which might overcome the attenuation, may require a continuous supply of high energy, may be inefficient and may be in conflict with regulatory considerations.
Therefore, there is a need for an in-vivo sensing device, such as an imaging device, which may transmit data at efficient power levels.